U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database

Geologic Unit: Wisconsin

Usage:

Wisconsin Episode (IL,IN,IA,MI,MN,OH,WI)
A time-transgressive (diachronic) term applied to glacial-related deposits of the north-central U.S.


Subunits:

(ascending) --all in IL: Athens Subepisode, Michigan Subepisode.


Geologic age:

Quaternary (Pleistocene; Sangomanian to Wisconsinan Age)


Type section, locality, area and/or origin of name:

[Type area: Lake Michigan Lobe extending from south of Peoria, IL, to Straits of Mackinac, MI, encompassing the type sections of the constituent lithostratigraphic units (see Hansel and Johnson, 1996).]


AAPG geologic province:

Illinois basin
Michigan basin
Wisconsin arch


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates usage by the U.S. Geological Survey. Other usages by state geological surveys.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).